1. Field
This invention relates to computer animation and computer vision. Specifically, this invention relates to a method and system for controlling an avatar.
2. General Background and Related Art
A two- or three-dimensional (3D) computer-animated character such as an avatar may be controlled in a number of ways. For example, in the computer game industry, a character may be controlled via an input device such as a control pad. In a graphical interface, an avatar may be controlled via a mouse or a combination of a mouse and a keyboard. Although limited training may be sufficient to teach users how to operate such control devices, translating various actions performed on such control devices to corresponding animated acts is often neither intuitive nor natural.
Attempts have been made to achieve animated character control based on human gestures. A human user may make certain gestures that correspond to certain control signals. Such gestures may be detected and interpreted via automatic means. For example, video frames of a human user making different gestures may be captured and analyzed so that relevant gestures can be identified and understood. The interpretation of the detected gestures is then used to control the movement of an animated character such as an avatar.
To detect a user""s gestures, it is often necessary to first detect where the user is located and when the user makes gestures. Distinctive marks may be used to effectuate detection of the user. Examples of such marks include special clothing, clothing with colored artifacts, or special devices such as infrared tags. As such, the user must wear or carry marks that are obtainable and distinguishable from the user""s surroundings. Automated processing identifies these distinctive marks from the images, notes location and movement of the marks, and infers what gestures occurred. Since these approaches require a user to wear marks, the user may feel inconvenienced or uncomfortable.
Another approach requires users to make gestures at predefined positions. While this approach does not require the user to wear or carry marks, it forces the user to memorize the correspondence between different positions and control effects.
Therefore, what is needed is a method and system to control an avatar in a more natural and direct manner.